阅读说明：本技术 一种应用于cfb锅炉的循环灰冷灰装置及其使用方法 (Circulating ash cooling device applied to CFB boiler and application method thereof ) 是由 赵鹏勃 茹宇 李楠 高洪培 王海涛 孙献斌 袁野 李昱喆 林伟荣 于 2020-07-31 设计创作，主要内容包括：本发明公开一种应用于CFB锅炉的循环灰冷灰装置机及其使用方法,包括回料阀、锥形阀和冷灰器,其中,锥形阀设置在回料阀的出口处,锥形阀的出口与冷灰器的循环灰入口连接；冷灰器用于冷却循环灰,冷却后的循环灰通过冷灰器的循环灰出口排出。本发明根据锅炉实际运行工况灵活调整入炉灰量,保证燃用高灰分煤种时锅炉良好的灰平衡特性。本发明提供的冷灰装置通过冷却水对冷灰器内的循环灰进行充分冷却,实现循环灰热量的利用,不降低锅炉热效率,并且结构简单,无需对锅炉本体进行改造,成本低廉,易于工业化实现。(The invention discloses a circulating ash and cold ash device applied to a CFB boiler and a using method thereof, wherein the circulating ash and cold ash device comprises a material returning valve, a conical valve and an ash cooler, wherein the conical valve is arranged at an outlet of the material returning valve, and an outlet of the conical valve is connected with a circulating ash inlet of the ash cooler; the ash cooler is used for cooling the circulating ash, and the cooled circulating ash is discharged through a circulating ash outlet of the ash cooler. The invention flexibly adjusts the amount of the ash entering the boiler according to the actual operation condition of the boiler, and ensures the good ash balance characteristic of the boiler when high ash content coal is used. The ash cooling device provided by the invention can be used for fully cooling the circulating ash in the ash cooler through the cooling water, so that the heat of the circulating ash is utilized, the heat efficiency of the boiler is not reduced, the structure is simple, the body of the boiler is not required to be modified, the cost is low, and the industrial implementation is easy.)

1. A circulating ash and cold ash device applied to a CFB boiler is characterized by comprising a material returning valve (10), a conical valve (12) and an ash cooler (14), wherein the conical valve (12) is arranged at an outlet of the material returning valve (10), and an outlet of the conical valve (12) is connected with a circulating ash inlet of the ash cooler (14); the ash cooler is used for cooling the circulating ash, and the cooled circulating ash is discharged through a circulating ash outlet of the ash cooler (14).

2. The circulating ash and cold ash device applied to the CFB boiler is characterized in that the ash cooler (14) comprises an outer sleeve (141) and an inner sleeve (142), the inner sleeve (142) is formed by welding a plurality of tube bundles with fins therebetween, the inner sleeve (142) is integrally and fixedly arranged on the inner wall of the outer sleeve, a demineralized water inlet of the ash cooler (14) is connected with a demineralized water outlet of the demineralized water tank (15) through a first demineralized water pump (161), the tube bundles of the inner sleeve (141) are used for circulating demineralized water, and the inner side of the inner sleeve is used for circulating ash.

3. The circulating ash and ash cooling device applied to the CFB boiler is characterized in that chain transmission protrusions are arranged at two ends of the outer wall of the outer sleeve (142), a chain transmission mechanism is arranged on the base of the ash cooler (14), and the chain transmission protrusions are matched with the chain transmission mechanism to realize the rolling of the ash cooler and improve the ash cooling efficiency.

4. The circulating ash and cold ash device applied to the CFB boiler is characterized in that the cone valve (12) comprises a valve plug (121), a valve seat (122), a water cooling jacket valve rod (123), a hydraulic actuator (124) and a valve body (125), wherein one end of the valve body (125) is connected with an outlet of the material returning valve (10), the valve seat (122) is arranged in the valve body (125) at the end of the valve body (125) connected with the material returning valve (10), the valve plug (121) is arranged between the valve seats (122) and is in fit contact with the valve seat (122), the hydraulic actuator (124) is arranged outside the valve body (125), the output end of the hydraulic actuator (124) is connected with one end of the water cooling jacket valve rod, the other end of the water cooling jacket valve rod (123) extends into the valve body (125) and is connected with the valve plug (121), the hydraulic actuator (124) is used for controlling the water cooling valve rod (124) to move back and forth to drive the movement, the valve plug (121) and the valve seat (122) are matched with each other to realize the closing or opening of the conical valve.

5. A circulating ash and cold ash device applied to CFB boiler as claimed in claim 4, wherein the valve plug (121), valve seat (122) are made of refractory material; refractory materials are laid on the inner side of the valve body (125) and the inner side of the pipe wall of the ash falling pipe (13); and a water cooling device is additionally arranged on the outer layer of the water cooling sleeve valve rod (123) for cooling.

6. A circulating ash and cold ash device applied to a CFB boiler, as claimed in claim 1, wherein said feed back valve (10) is connected with the circulating ash outlet of the separator (9), the inlet of the separator (9) is connected with the upper outlet of the furnace (1), the flue gas outlet of the separator (9) is connected with the back flue (18), the outlet of the back flue (18) is connected with the dust remover (19), and the outlet of the dust remover (19) is connected with the chimney (20); the material returning valve (10) is provided with two outlets, the outlet close to one side of the hearth (1) is connected with the lower part of the hearth (1) through a material returning leg (11), the outlet far away from one side of the hearth (1) is provided with a conical valve (12), and the outlet of the conical valve (12) is connected with a circulating ash inlet of an ash cooler (14) through an ash dropping pipe (13).

7. The circulating ash and cold ash device applied to the CFB boiler is characterized in that a slag discharge port (2) is formed in the bottom of the hearth (1), and the slag discharge port (2) is connected with a slag falling pipe (3); the slag pipe (3) that falls is through push-pull valve (4) and the entry linkage of advancing sediment pipe (5), the exit linkage that advances sediment pipe (5) has the end sediment entry of cold sediment ware (6), the end sediment exit linkage of cold sediment ware (6) is gone out slag pipe (7), the export setting of the pipe of going out slag (7) is in the top of defeated sediment belt (8).

8. The circulating ash and cold ash device applied to a CFB boiler of claim 7, wherein the demineralized water inlet of the slag cooler (6) is connected with the demineralized water outlet of the demineralized water tank (15) through a second demineralized water pump (162), and the demineralized water outlet of the slag cooler (6) is connected with the condensate system (17).

9. A circulating ash cooling ash device applied to CFB boiler according to claim 7, characterized in that the slag outlet (7) of the bottom slag outlet of the slag cooler (6) is connected with the circulating ash outlet of the ash cooler (14) for discharging the circulating ash to the slag conveying belt (8).

10. The use method of a circulating ash and cold ash device applied to a CFB boiler is characterized in that a material returning valve (10) leads part of high-temperature circulating ash in a separator (9) into an ash falling pipe (13) through a cone valve (12), the high-temperature circulating ash entering the ash falling pipe (13) enters the inner side of an inner sleeve (142) of an ash cooler (14), and demineralized water in a demineralized water tank (15) is introduced into a plurality of tube bundles of the inner sleeve (142) of the ash cooler (14) through a first demineralized water pump (162); the desalted water exchanges heat with the high-temperature circulating ash, and more sufficient heat exchange is realized through the rolling of the ash cooler; the desalted water in the desalted water tank (15) is introduced into the slag cooler (6) through a second desalted water pump (162), and the desalted water entering the slag cooler (6) exchanges heat with the boiler bottom slag in the slag cooler (6); the cooled circulating ash and the cooled boiler bottom slag are discharged to a slag conveying belt from a slag discharging pipe (7) together; the desalted water after heat exchange is led into a condensate system (17) for recovery.

Technical Field

The invention relates to the technical field of circulating fluidized bed boilers, in particular to a circulating ash cooling device applied to a CFB boiler and a using method thereof.

Background

At present, a Circulating Fluidized Bed (CFB) boiler generally reduces bed temperature through low-nitrogen combustion and efficiency improvement of a separator, so that the desulfurization and denitrification cost is reduced, the economic operation of the boiler is realized, and the efficiency improvement of the separator and the bed temperature reduction are mainly realized by adding circulating ash into the boiler and increasing the material quantity in the boiler. However, for a CFB boiler partially burning high-ash coal, because the material stock in a boiler furnace is too large and the bed temperature level is too low, a series of problems of difficult load carrying of the boiler, high content of ash and slag combustible, low boiler efficiency and the like are caused. Particularly, at low load, the operating bed pressure of the boiler is high due to large material quantity and low bed temperature, the fluidization condition of the materials is deteriorated when the operating bed pressure is serious, and the bed surface is coked at low temperature and even collapses, so that the safe operation of the boiler is endangered.

Disclosure of Invention

In order to solve the problems of overlarge circulating ash amount, overlarge material storage in a furnace and the like when the circulating fluidized bed boiler burns high-ash coal types, the invention provides a circulating ash cooling ash device applied to a CFB (circulating fluidized bed) boiler and a using method thereof, which can flexibly adjust the ash amount entering the boiler and ensure the good ash balance characteristic of the circulating fluidized bed boiler when the high-ash coal types are burnt.

The invention provides a circulating ash and cold ash device applied to a CFB (circulating fluid bed) boiler, which comprises a material returning valve, a conical valve and an ash cooler, wherein the conical valve is arranged at an outlet of the material returning valve, and an outlet of the conical valve is connected with a circulating ash inlet of the ash cooler; the ash cooler is used for cooling the circulating ash, and the cooled circulating ash is discharged through a circulating ash outlet of the ash cooler.

Further, ash cooler includes outer sleeve and inner skleeve, the inner skleeve comprises welding fin between a plurality of tube bundles, the whole welding of inner skleeve is on the outer sleeve inner wall, be used for the demineralized water that circulates in the inner skleeve tube bundle, the inner skleeve inboard is used for circulating the circulation ash.

Furthermore, chain transmission bulges are arranged at two ends of the outer wall of the outer sleeve, a chain transmission mechanism is arranged on the base of the ash cooler, and the chain transmission bulges are matched with the chain transmission mechanism to realize the rolling of the ash cooler and improve the ash cooling efficiency; the rotation of the ash cooler is driven by a corresponding servo motor; the ash cooler is arranged at a certain angle and is used for facilitating circulation of circulating ash.

Further, the cone valve includes valve plug, disk seat, water-cooling jacket valve rod, hydraulic actuator and valve body, wherein, the one end and the feed back valve exit linkage of valve body, just be provided with the disk seat in the valve body of the one end that valve body and feed back valve are connected, the valve plug sets up mutually support the contact with the disk seat between the disk seat, the valve body outside is provided with hydraulic actuator, hydraulic actuator's output with the one end of water-cooling jacket valve rod is connected, the other end of water-cooling jacket valve rod stretch into in the valve body and with the valve plug is connected, hydraulic actuator is used for controlling water-cooling valve rod back-and-forth movement and drives the valve plug and removes, the valve plug mutually supports with the disk seat and realizes the closure or.

Further, the valve plug and the valve seat are made of refractory materials, and the refractory materials are X15CrNiSi2520 heat-resistant steel; refractory materials are laid on the inner side of the valve body and the inner side of the pipe wall of the ash falling pipe, and the laid refractory materials are high-aluminum wear-resistant castable materials; and the water cooling device is additionally arranged on the outer layer of the water cooling sleeve valve rod for cooling.

Furthermore, the feed back valve is connected with a circulating ash outlet of a separator, an inlet of the separator is connected with an outlet at the upper part of the hearth, a flue gas outlet of the separator is connected with a tail flue, an outlet of the tail flue is connected with a dust remover, and an outlet of the dust remover is connected with a chimney; the feed back valve is provided with two outlets, the outlet close to one side of the hearth is connected with the lower part of the hearth through a feed back leg, and the outlet far away from one side of the hearth is provided with a conical valve.

Further, a slag discharge port is arranged at the bottom of the hearth and is connected with a slag falling pipe; the slag falling pipe is connected with an inlet of the slag inlet pipe through a gate valve, an outlet of the slag inlet pipe is connected with a bottom slag inlet of the slag cooler, a bottom slag outlet of the slag cooler is connected with a slag outlet pipe, and an outlet of the slag outlet pipe is arranged above the slag conveying belt.

Furthermore, a cooling water inlet of the slag cooler is connected with the desalting water tank through a second desalting water pump, and a cooling water outlet of the slag cooler is connected with the condensed water system.

Furthermore, a slag outlet pipe connected with a bottom slag outlet of the slag cooler is communicated with a circulating ash outlet of the ash cooler and used for discharging circulating ash to a slag conveying belt together with boiler bottom slag discharged by the slag cooler.

The invention also provides a use method of the circulating ash and cold ash device applied to the CFB boiler, which comprises the steps that the return valve leads part of high-temperature circulating ash in the separator through a conical valve, the high-temperature circulating ash led by the conical valve enters an ash falling pipe, the high-temperature circulating ash entering the ash falling pipe enters the inner side of an inner sleeve of the ash cooler, demineralized water in a demineralized water tank is introduced into a plurality of pipe bundles of the inner sleeve of the ash cooler through a first demineralized water pump, chain transmission bulges are arranged at two ends of the outer wall of the outer sleeve of the ash cooler, a chain transmission mechanism is arranged on a base of the ash cooler, the chain transmission bulges are matched with the chain transmission mechanism to realize the rolling of the ash cooler, and the demineralized water entering the inner sleeve pipe exchanges heat with the high-temperature circulating ash entering the inner sleeve of the ash cooler; introducing the demineralized water in the demineralized water tank into the slag cooler through a second demineralized water pump, and exchanging heat between the demineralized water entering the slag cooler and the boiler bottom slag in the slag cooler; the cooled circulating ash is discharged into a slag discharging pipe connected with a bottom slag outlet of the slag cooler through a circulating ash outlet of the ash cooler, the cooled boiler bottom slag is discharged into the slag discharging pipe through a low slag outlet of the slag cooler, an outlet of the slag discharging pipe is arranged above the slag conveying belt, and the cooled circulating ash and the cooled boiler bottom slag are discharged onto the slag conveying belt together; and introducing the desalted water subjected to heat exchange into a condensate system for recycling.

Compared with the prior art, the invention has at least the following beneficial effects:

(1) the ash cooling device provided by the invention comprises the conical valve and the ash cooler, the conical valve can flexibly adjust the opening of the conical valve according to the actual operation condition of the boiler so as to control the amount of ash entering the boiler, and the conical valve has better control characteristic and sealing characteristic and can ensure the good ash balance characteristic of the boiler when high-ash coal is combusted; the cooling area of a plurality of tube bank welding fins's design increase inner skleeve in the inner skleeve is passed through to the ash cooler, and the roll of ash cooler is fully cooled off the high temperature circulation ash in the ash cooler simultaneously when circulating ash cooling to improve boiler efficiency, guarantee boiler operation security and stability, improve its feature of environmental protection.

(2) Because the temperature of the circulating ash is lower than that of the bottom slag, the circulating ash is cooled by the desalted water circulating through the inner tube bundle, the desalted water absorbs the heat of the circulating ash while cooling the circulating ash, the desalted water absorbing the heat enters a condensate system, the initial temperature of a condensate outlet is increased, steam used for heating subsequent condensate is reduced, the heat of the circulating ash is utilized, and the thermal efficiency of a boiler is not reduced; in addition, the invention adopts the desalted water as the cooling medium, so that the corrosion of the cooling medium to the inner wall of the tube bundle of the ash cooler can be reduced, and the material cost for manufacturing the ash cooler is reduced.

(3) The ash cooler provided by the invention realizes the rolling of the ash cooler through the mutual matching of the chain transmission bulges arranged on the outer wall of the outer sleeve and the chain transmission mechanism arranged on the base of the ash cooler, the rolling can improve the heat transfer coefficient, increase the heat transfer area and disturbance and improve the ash cooling efficiency; the ash cooler is installed at a certain angle, so that the circulating ash is conveniently discharged; the ash cooler provided by the invention has the advantages of simple structure, low manufacturing difficulty, low cost and easiness in industrial realization, and can be used without modifying a boiler body.

(4) The boiler bottom deslagging port is mainly used for discharging slag blocks with larger particles, the fine particles in normal operation enter the separator along with the flue gas leaving the hearth and return to the hearth in a large proportion, and when the ash content of coal is higher, the circulating ash content is large along with the operation of the boiler; the invention also utilizes the existing slag discharge belt to discharge the cooled circulating ash and the boiler bottom slag together, thereby saving the investment cost.

Drawings

FIG. 1 is a circulating ash and cold ash apparatus for use in a CFB boiler;

FIG. 2 is a block diagram of a cone valve used in a circulating ash and cold ash apparatus of a CFB boiler;

FIG. 3 is a block diagram of an ash cooler in a circulating ash cooling device for a CFB boiler.

In the drawings: 1, a hearth; 2, a slag discharge port; 3, a slag falling pipe; 4, a gate valve; 5, a slag inlet pipe; 6, a slag cooler; 7, a slag discharging pipe; 8, conveying a slag belt; 9 a separator; 10 a material return valve; 11 a return leg; 12 a cone valve; 121 a valve plug; 122 a valve seat; 123 water-cooling jacket valve rod; 124 hydraulic actuators; 125 a valve body; 13 a dust falling pipe; 14, an ash cooler; 141 an outer sleeve; 142 an inner sleeve; 15 a demineralized water tank; 161 a demineralized water pump; 162 a demineralized water pump; 17 a condensate system; 18 tail flues; 19 a dust remover; 20 chimney.

Detailed Description

The invention provides a circulating ash cooling device applied to a CFB boiler and a using method thereof, which are further described in the following by combining the attached drawings and the detailed description.

A circulating ash cooling ash device applied to a CFB boiler is shown in FIG. 1, wherein an upper outlet of a hearth 1 is connected with an inlet of a separator 9, a circulating ash outlet of the separator 9 is connected to a feed back valve 10, and a flue gas outlet is connected to a tail flue 18; the material returning valve 10 is provided with two outlets, the outlet close to one side of the hearth 1 is connected with the lower part of the hearth 1 through a material returning leg 11, the outlet far away from one side of the hearth is provided with a conical valve 12, and the outlet of the conical valve 12 is connected to a circulating ash inlet of an ash cooler 14 through an ash dropping pipe 13;

in this embodiment, the demineralized water inlet of the ash cooler 14 is connected to the demineralized water outlet of the demineralized water tank 15 through the first demineralized water pump 161, the first demineralized water pump 161 delivers the demineralized water to the cooling water inlet of the ash cooler 14, the demineralized water exchanges heat with the circulating ash in the ash cooler 14, and the demineralized water after heat exchange enters the condensate system 17 from the cooling water outlet of the ash cooler 14;

in the embodiment, the bottom of a hearth 1 is provided with a slag discharge port 2, and the slag discharge port 2 is connected with a slag falling pipe 3; the slag falling pipe 3 is connected with a slag inlet pipe 5 through a gate valve 4; the outlet of the slag inlet pipe 5 is connected with the bottom slag inlet of the slag cooler 6, and the bottom slag outlet of the slag cooler 6 is communicated to the upper part of the slag conveying belt 8 through the slag outlet pipe 7; the cooling water inlet of the slag cooler 6 is connected with the demineralized water tank 15 through the second demineralized water pump 162, the cooling water outlet of the slag cooler 6 is connected with the condensate system 17, the second demineralized water pump 162 conveys demineralized water to the cooling water inlet of the slag cooler 5, the demineralized water exchanges heat with the boiler bottom slag of the slag cooler 6, the demineralized water after the heat exchange enters the condensate system 17 from the cooling water outlet of the slag cooler 6, and the boiler water condensate system 17 recovers the demineralized water.

Specifically, a circulating ash outlet of the ash cooler 14 is communicated with a slag discharging pipe 7 connected with an outlet of the slag cooler 6, the cooled circulating ash is discharged into the slag discharging pipe 7 by the ash cooler 14, and the cooled circulating ash falls to the slag conveying belt 8 along with bottom slag discharged by the slag cooler 6.

As shown in fig. 2, the conical valve 12 of the present embodiment includes a valve plug 121, a valve seat 122, a water jacket valve stem 123, a hydraulic actuator 124 and a valve body 125, wherein the valve body 125 is welded at the outlet of the side wall of the material return valve 10, the valve body 125 at the end of the valve body 125 connected with the material return valve 10 is provided with the valve seat 122, it can be seen from fig. 2 that the valve plug 121 is clamped in the channel formed by the valve seat 122, the valve plug 121 and the valve seat 122 are in mutual matching contact, the exterior of the valve body 125 is provided with the hydraulic actuator 124, the output end of the hydraulic actuator 124 is connected with one end of the valve stem of the water-cooling jacket, the other end of the water-cooling jacket valve rod 123 extends into the valve body 125 and is connected with the valve plug 121, the hydraulic actuator 124 drives the valve plug 121 to move by controlling the water-cooling valve rod 123 to move back and forth, so as to realize the control of the relative position between the valve plug 121 and the valve seat 122, thereby adjusting the flow capacity of the conical valve 12 and varying the flow rate of the circulating ash in the loop seal 10 through the conical valve 12.

As shown in fig. 3, the ash cooler 14 in this embodiment includes an outer sleeve 141 and an inner sleeve 142, the inner sleeve 142 is formed by welding fins between a plurality of tube bundles, the inner sleeve 142 is integrally welded on the inner wall of the outer sleeve 141, demineralized water flows through the tube bundles of the inner sleeve 142, circulating ash flows through the inner side of the inner sleeve 142, and the demineralized water cools and exchanges heat with the circulating ash. In order to facilitate circulation and discharge of circulating ash, the ash cooler 14 is inclined at a certain angle when being installed, meanwhile, chain transmission protrusions are arranged at two ends of the outer wall of the outer sleeve 141, a chain transmission mechanism is arranged on the base of the ash cooler 14, and the chain transmission protrusions and the chain transmission mechanism are matched with each other to realize rolling of the ash cooler 14 and improve cooling efficiency of the ash cooler; the rotation of the ash cooler 14 is driven by a corresponding servomotor.

Furthermore, both ends at the ash cooler are provided with a rotary joint respectively, and a plurality of tube bundles of ash cooler inner skleeve assemble into a demineralized water inlet pipe and a demineralized water outlet pipe respectively at ash cooler both ends, and two pipelines all are connected with rotary joint, and the entering and the discharge of demineralized water when realizing ash cooler is rotatory.

Preferably, the valve plug 121 and the valve seat 122 of the conical valve 12 of the present embodiment are made of wear-resistant and refractory materials, including but not limited to X15CrNiSi2520 heat-resistant steel; a water cooling jacket is additionally arranged on the outer layer of the water cooling jacket valve rod 123 for cooling; refractory materials including but not limited to high-aluminum wear-resistant castable are laid on the inner side of the valve body 125 and the inner side of the pipe wall of the circulating ash dropping pipe 13, so that the conical valve 12 is ensured to have a long service life.

When the device is used for cooling the circulating ash, the material returning valve 10 leads part of the high-temperature circulating ash in the separator 9 through the cone valve and the ash falling pipe to the inner sleeve 142 of the ash cooler 14, the first demineralized water pump 161 pumps the demineralized water in the demineralized water tank 15 into the inner sleeve 142 tube bundle of the ash cooler 14, chain transmission bulges are arranged at two ends of the outer wall of the outer sleeve 141 of the ash cooler 14, a chain transmission mechanism is arranged at the base of the ash cooler 14, the chain transmission protrusion and the chain transmission mechanism are mutually matched for realizing the rolling of the ash cooler 14, the ash cooler rolls continuously in the process of heat exchange and temperature reduction of the high-temperature circulating ash by the desalted water, so that the ash cooling efficiency can be improved, the cooled circulating ash passes through the slag discharging pipe 7 discharged from the circulating ash outlet of the ash cooler 14, the demineralized water in the demineralized water tank 15 is introduced into the slag cooler 6 through the second demineralized water pump 162, and the demineralized water entering the slag cooler 6 exchanges heat with the boiler bottom slag in the slag cooler 6; the cooled circulating ash is discharged into a slag discharging pipe 7 connected with a bottom slag outlet of a slag cooler 6 through a circulating ash outlet of an ash cooler 14, the cooled boiler bottom slag is discharged into the slag discharging pipe 7 through a low slag outlet of the slag cooler 6, an outlet of the slag discharging pipe 7 is arranged above a slag conveying belt 8, and the cooled circulating ash and the cooled boiler bottom slag are discharged onto the slag conveying belt 8 together; the desalted water after heat exchange is introduced into a condensate system 17 for recovery.